A morphometric analysis of rat ventral prostate in organ culture.

A stereologic, morphometric method was used for determining the quantitative and qualitative changes in the rat ventral prostate during organ culture. The volume density of epithelium (VVEP), lumina (VVLU), and interstitium (VVIT) as well as the proportion of epithelium of the tissue, VVEP/(VVEP + VVIT), the length density of tubular structures (LV), mean diameter of the lumina (DLU), height of the epithelium (h), and mean width of the interacinar tissue (lambda AP) were evaluated. In the perfusion-fixed prostate these parameters gave the closest approximation for the in vivo situation: VVEP was 0.19 mm3/mm3; h 19.5 micron; VVEP/(VVEP + VVIT) 0.63 mm3/mm3; VVLU 0.70 mm3/mm3; DLU 230 micron; VVIT 0.11 mm3/mm3; lambda AP 84.1 micron; and LV 17.5 mm/mm3. Dissection of the prostate for culture caused leakage of prostatic secretions and a consequent diminution of VVLU (0.41 mm3/mm3) and DLU (151 micron), as well as folding of the epithelium and distortion of the interacinar tissue (VVIT 0.25 mm3/mm3). During 10 days culture in a defined medium, the prostate underwent involutive changes including loss of total weight, a decrease of VVEP, and an increase of VVIT. During the first day a stimulatory effect on the epithelium occurred, which might have been caused by a loss of androgenic control or by substances in leaking secretions. Testosterone postponed many of these changes and maintained the secretory function better. Thus, on day 4 the morphology of the prostate resembled better the situation in vivo than at the beginning of involutionary culture. However, later during culture changes, similar to those found without testosterone but weaker, were noted. Statistical analysis of data showed that it is more advisable to use many pieces from one prostate lobe rather than to use many animals. Analysis of one slice is also sufficient to give relevant data on that piece.